From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id ACD5AC25B78 for ; Wed, 22 May 2024 14:56:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0753F6B0083; Wed, 22 May 2024 10:56:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F18226B0088; Wed, 22 May 2024 10:56:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DDFFB6B0089; Wed, 22 May 2024 10:56:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id BFE0A6B0083 for ; Wed, 22 May 2024 10:56:41 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 552B7121EA7 for ; Wed, 22 May 2024 14:56:41 +0000 (UTC) X-FDA: 82146333402.16.7F991C2 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf30.hostedemail.com (Postfix) with ESMTP id A3C4B80009 for ; Wed, 22 May 2024 14:56:39 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=sOGTz7oy; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf30.hostedemail.com: domain of djwong@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=djwong@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1716389799; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=x48OGkp+bXW0UYBVLjfdduW/hXyI9ec4rEFI4TIft64=; b=zibOWSc9kSxC8IINmz9uz9w7YeiPjHO/+lBa3hMQ3hI7C13NIlxx4f+EXXeq9oC7/sx6s9 nJTFQ7v1SycUMCOA4raNVuVq+x1eMnYFHXdeSUJuMzDugPmkAF8eQ5nGbDPaMAUIzGHY1G wLW2p7kywOyhebtxh/4eFZgZr0ZSiXw= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=sOGTz7oy; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf30.hostedemail.com: domain of djwong@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=djwong@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1716389799; a=rsa-sha256; cv=none; b=Q8hp8NFibcD2u8/O5Fy1buHju43qqN0C624mjgaRHjx1ck9YMWkg4X9fPJTlm4wDuIP/iG fNVHc39noFZLrTVdmH0H8kMcgyvXr3zVre1LH9JQbfAHCSuLcKJCH2oXzjy/58rnQXE2b1 TIiem1TKgVZ3gzcVH7Eoh7U10FrjQF8= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 9468C62A26; Wed, 22 May 2024 14:56:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 415E3C2BBFC; Wed, 22 May 2024 14:56:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1716389798; bh=zWm8NiSY2+aawW2KRUHKXAJ/95lx4gCIUjpIrTP/ufc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=sOGTz7oynf65RXL6PVaStX562gyTyqhuRcDAIstxAgUBzOyhuqL9yJvvd1on9/nyv 2POi+KESaZ7+I1qt3oo8po9UUfh1Y1clhy+vtovEWSrXmtX4ORJHWVQE1abZ+SdTHd qv2umpzSHjBXMTTiGYbq4lJ1r6e8+l/Cek2UlHdoca/16QAn0WPvI7VxA9PymwLMpt q/Vu7I5TUwCiScpmepGhVnIRhRJonYO2/e4jwzh7aEFTRkGV32sjmW2Epfk9gASBdi 90yeF0mQGFjHZpttSXuC0+gC6dXSrB1UzV4Q1iUDrf13hGLkjWhW+35KEY/mzNUkU3 /NZbFLelIBbnQ== Date: Wed, 22 May 2024 07:56:37 -0700 From: "Darrick J. Wong" To: Sukrit Bhatnagar Cc: "Rafael J. Wysocki" , Pavel Machek , Christian Brauner , Andrew Morton , linux-xfs@vger.kernel.org, linux-pm@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 2/2] mm: swap: print starting physical block offset in swapon Message-ID: <20240522145637.GV25518@frogsfrogsfrogs> References: <20240522074658.2420468-1-Sukrit.Bhatnagar@sony.com> <20240522074658.2420468-3-Sukrit.Bhatnagar@sony.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240522074658.2420468-3-Sukrit.Bhatnagar@sony.com> X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: A3C4B80009 X-Stat-Signature: djm3zewcgfphxfkfjubpxmgthhx13r4q X-HE-Tag: 1716389799-67524 X-HE-Meta: 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 vcBf+B8N dkqj+3y9C8wgnjwsy76eeBbWzAH0Fzsbt4r81i1EM+LhTiVHGpy6Ck5vtL+4pQgGYBZcWXYre7JhDnFhEA3lWF/MxRSTyG/TgomVc4j+4GAMuUGfy8lpLJDutVqZ+hQ/O341PDP8fjtUQMa7lkhi9mqztRYIhlyzqp71oq/B1RrwbWt0Ix7pJqsJiJypkUEPwysdRb+eXRJJe3MfIYGqFuP4gdUS0QOHIA6cbzfzu33l8vL+DVE4p6F8I8Q== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, May 22, 2024 at 04:46:58PM +0900, Sukrit Bhatnagar wrote: > When a swapfile is created for hibernation purposes, we always need > the starting physical block offset, which is usually determined using > userspace commands such as filefrag. If you always need this value, then shouldn't it be exported via sysfs or somewhere so that you can always get to it? The kernel ringbuffer can overwrite log messages, swapfiles can get disabled, etc. > It would be good to have that value printed when we do swapon and get > that value directly from dmesg. > > Signed-off-by: Sukrit Bhatnagar > --- > mm/swapfile.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/mm/swapfile.c b/mm/swapfile.c > index f6ca215fb92f..53c9187d5fbe 100644 > --- a/mm/swapfile.c > +++ b/mm/swapfile.c > @@ -3264,8 +3264,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) > (swap_flags & SWAP_FLAG_PRIO_MASK) >> SWAP_FLAG_PRIO_SHIFT; > enable_swap_info(p, prio, swap_map, cluster_info); > > - pr_info("Adding %uk swap on %s. Priority:%d extents:%d across:%lluk %s%s%s%s\n", > + pr_info("Adding %uk swap on %s. Priority:%d extents:%d start:%llu across:%lluk %s%s%s%s\n", > K(p->pages), name->name, p->prio, nr_extents, > + (unsigned long long)first_se(p)->start_block, Last time I looked, start_block was in units of PAGE_SIZE, despite add_swap_extent confusingly (ab)using the sector_t type. Wherever you end up reporting this value, it ought to be converted to something more common (like byte offset or 512b-block offset). Also ... if this is a swap *file* then reporting the path and the physical storage device address is not that helpful. Exposing the block device major/minor and block device address would be much more useful, wouldn't it? (Not that I have any idea what the "suspend process" in the cover letter refers to -- suspend and hibernate have been broken on xfs forever...) --D > K((unsigned long long)span), > (p->flags & SWP_SOLIDSTATE) ? "SS" : "", > (p->flags & SWP_DISCARDABLE) ? "D" : "", > -- > 2.34.1 > >